Top retaining bolt does not have Allen bolt or bolt to remove?

If the top retaining bolt lacks an Allen or traditional bolt head for removal, it may be a security or tamper-proof fastener. Check for any visible notches or patterns that could indicate a specialized tool is needed. Alternatively, it might be a press-fit or snap-fit design, requiring gentle prying or pulling to release. Always consult the manufacturer's manual for specific guidance on disassembly.